Question

Briannas teacher ask her which of these three expressions is equivalent to each other
Expression A: 9x-3x-4
Expression B: 12x-4
Expression C: 5x+x-4
Brianna says it is all correct
Identify the error in Briannas thinking

Answer 1

Expression A

9x-3x-4 = 6x-4

Expression B

12x-4

Expression C

5x+x-4= 6x-4

Expression A = Expression C = 6x-4